Room Placement and Bass LSR32 or LSR6332?

[Minatogawaman]

I'm looking for advice on room placement of my LSR6332 to extend bass response. JBL lists the bottom end as 60Hz for these wonderful speakers. I have read elsewhere that proper room placement (against walls and corners) can extend bass response as far as 40Hz. On this system we listen to mostly classical, acoustic jazz and acoustic folk on LP records so 40Hz is probably low enough. Does this sound accurate?

My living room is about 12 feet across (and 10 feet long) with a LSR6632 in each corner angled slightly inward on 2-inch-thick solid cherry stands about 20-inches high. (The room is connected to a dining room about the same size but slightly offset). Does anyone have advice for placement to maximize bass in this environment?

Sadly, my budget would not allow for the LSR6312 sub(s) for the living room system. (Have one in the studio with LSR28p and it sounds great in the living room too, but ran out of budget).

The LSR6332 are powered by an Antique Sound Labs AQ1003DT integrated (EL34. 12AU7 tube amp). This integrated has a "subout" but it is full range (not crossed over). I would consider buying some LF 15" or 12" drivers from the JBL tent sale and making my own subs (have a extra power amp), but if placement can resolve the problem I'd like to be spared the cost and wifely aggravation.

Thank you for your advice!

Minatogawaman
Takasaki City, Japan

[mikebake]

Yer driving them with a tube amp? Theres your problem...........
Additionally, the forward mid tends to detract from the bass performance, IMO.

[LowPhreak]

Yer driving them with a tube amp? Theres your problem...........

I disagree. You just gotta have the right tube amp, eg: VTL, Manley, Mesa, big-assed Audio Research, etc. But it is easier/cheaper to get decent bass output from SS.


Minatogawaman -

One of the first things I'd do is isolate the speakers on the most solid, vibration-free device I could find/afford, like Sound Anchors stands. Though they might look nice, 2" thick cherry is nothing to write home about when it comes to vibe isolation. You drain the vibration from the cabinet, (or prevent them from vibrating in the first place) and your low end is going to be much cleaner and probably louder, but perhaps not enough louder to get where you want to be. I've found however that good speaker isolation can do wonders for the overall response.

You could experiment with speaker height from the floor, because sometimes you'll get a floor reflection that cancels out certain frequencies, ie, maybe 20" is not the optimal height for those speakers. Changing a few inches higher or lower sometimes makes a world of difference.

Placement in any room is fairly unpredictable since there are so many variables, but one starting point is to use "odd integers". I've found it to work OK in some rooms.

Let's say you have the speakers placed along the 12' wall, and you want to find how far away from that wall you should place them. Divide 12' by 3, 5, 7, 9, etc. to get the distance from the back wall to the center of the front baffle, so:

3 = 48", 5 = 28.8", 7 = 20.6", 9 = 16"

...the idea being to avoid peaks and dips in the bass response, as well as at other freqs. You can do the same to determine placement from the side walls. Take the 10' wall and divide by 3, 5, 7, etc., so 7 = 17.1" or 5 = 24" from the center of the speaker to the side wall.

You have to do the work of moving the speakers around to different positions and listen, because this may or may not work well in in your room with your system.

[Minatogawaman]

I appreciate your replies and advice. My tube amp is admittedly a cheapie, but I like the way it sounds with my vinyl collection so, for now, these speakers are probably not going to be powered by SS. I run LSR32s in my home theater upstairs with an old Accuphase P-300s. The bass problem up there is less acute, in part perhaps, because I use a 15" JBL sub and probably due to SS amps driving the LSRs.

The idea of replacing the speaker stands and recalculating the position of the speakers was wonderful advice. I will try both. As much as the cherry stands appealed to me visually, I think I will make some metal stands based on the one's you recommend. I have access to a full-bore metal shop and a pro welder (my dad). Any recommendations on how I can dampen them?

Thanks again
Chris

[mikebake]

A 30 watt tube amp isn't going to give it to you with these speakers. The bass performance is symptomatic.
Recommended amplifier power starts at 150 and goes to 1000 for these, and there is a reason.
Adequately powered will make these rather different from what you are likely getting now. It matters to these as much as any speaker I've messed with in awhile.

[bone215]

Would it be possible to turn up the bass and see if it helps?

[LowPhreak]

Laff! Yeah, that always helps bone, but maybe he doesn't want to use or doesn't have tone pots or EQ. Myself, I like to try to find the best position in a room for a given set of speakers before I go monkeyin' with freq level adjustments. It is very possible to get a decent and likeable response curve without EQ'ing.

[LowPhreak]

The idea of replacing the speaker stands and recalculating the position of the speakers was wonderful advice. I will try both. As much as the cherry stands appealed to me visually, I think I will make some metal stands based on the one's you recommend. I have access to a full-bore metal shop and a pro welder (my dad). Any recommendations on how I can dampen them?

Thanks again
Chris

You're not thinking of fabricating one of SA's designs are you? Shame on you!

What I'd do first before settling on a final height is determine what the best height is for the LSR's in that room. For example, I'm using one of the predecessors to that speaker - the 4412 - and in this room they happen to like being about 26 1/2" from the floor when mounted horizontally. Any higher and the low end starts to get anemic; any lower and the ears are too far off-axis. Then I tilt the front baffles up on 3/4" speaker cones to get the tweets/mids pointing at the listener.

If you use steel tubing (as opposed to flat bar stock) you can fill it in with sand or lead shot to help damp the tubes and add mass. Leave a small hole in the top plates for that.

[Shane Shuster]

I think LowPhreak is offering very good advice. I also have a 10x12 listening room and have found the woofer height to be important. Too high up gives me very lean bass. I start with them on the floor and move them up little by little until a good compromise is met.

[mikebake]

"Normal" placement rules apply, but if you use sufficient power, you'll get your bass. Did I mention that before?

[LowPhreak]

mike -

Did not the OP mention this before?...

"My tube amp is admittedly a cheapie, but I like the way it sounds with my vinyl collection so, for now, these speakers are probably not going to be powered by SS."

Hence my recommending that he attempts to find the best placement possible b/c it costs nothing, except getting better stands which should be less than another amp or sub. He also may not have been aware of "normal placement rules".

[mikebake]

I understand. He just needs to know that the LSR's will never get there with that kind of power. That amp is wrung out before the LSR's are slightly involved.
He bought the S2000, now he has to run premium in it.

[LowPhreak]

Certainly with their 4 ohm impedance he'll need bigger current to get a good grip on those woofers. My problem with tubes is they can act like a big tone control if a particular amp doesn't happen to like your speaker's imp. curve. Then sometimes that can be a good thing.

And the LSR's don't have the typical in-room bump at 40-50Hz like the 4412/12A's have.

[mikebake]

He'd be hearing a different speaker with a strong high powered amp.

[speakerdave]

My LSR32's did not do well with my Audio Research VT60. Don't know why. That amp does well in the bass with other speakers. It may be the 4 ohm load. The LSR32's are within 1 dB from 60 Hz to the upper limit, which I think is around 20k. Accurate. Their 3 dB down point in the bass is 53 Hz. Most rooms start loading above that, so I think you should be subjectively hearing more bass. It's probably the amp. These speakers are biwired, so putting a solid state amp on the woofers would be quite easy. The JBL/UREI 6200 series would be a good low-cost option IF you can find a clean one. First, borrow a decent solid state amp to test the idea. I'm pretty sure you'll hear satisfactory bass for your kinds of music.

David